She also told "Access Hollywood" host Billy Bush that it's been a struggle to keep the news private.

"It's been a long journey, but it's been tough because I've been trying to have.... to hold onto a shred of privacy. And that was not easy," she said.

The singer said she's due in the spring, but wouldn't give an exact due date.

Cannon, 29, joined Carey during the interview to talk about the "absolutely emotional" news.

"The greatest gift on earth is a child," he told Bush. "But ... you know how much we have been through, you know."

Cannon was referring to Carey suffering a miscarriage, something that has not been made public until now. Two years ago, after the couple's wedding, they were in Monte Carlo for the World Music Awards when Carey took a pregnancy test that turned out positive.

"Only one person knew about this and we were like, um, 'let's not tell anybody else,'" Carey said.

The singer revealed that she miscarried a little more than a month later.

"It was really sad so we had to just, we had really to absorb this and take it in," Carey said.

Cannon added, "And that's what I said, like her strength would literally be during the day so festive and smiling obviously for cameras and spending time with everyone and you know, literally that night crying herself to sleep."

Bush added on "Today" that the couple said they conceived naturally and won't be finding out the sex of the baby before its birth.

Carey and Cannon have faced pregnancy rumors for months, as the two made coy references to pregnancy and babies in interviews and on Twitter. In June, Cannon wrote on his Twitter account that "If & when my wife is ready to make ANY announcements about private matters she will do it personally." The month before, he told a reporter that a member of his family was pregnant - his Jack Russell puppy Cha Cha.

In August, the rumors reached a frenzy when Carey was spotted in Brazil wearing a maternity dress. She addressed the speculation by explaining that she was "superstitious" and promising, "When the time is right, everyone will know."